After I saw inception I thought, the "totems" they use are obviously a form of Reality Checking. I think it would be reasonable to make some sort of small mark on your hand or arm that only you would really notice like a small square or circle.

The RC would go something like this,

You imagine looking at your arm or hand but the mark isnt there, try and imagine it clearly.

So, when you look for real you should go in EXPECTING no mark to be there in a way.

When you finally look, think to yourself "I must be awake..."

Could this method work?